drools 5.0.1 vs 6.0.1 API changes? - drools

We are upgrading our application from drools 5.0.1 to drools 6.0.1 Final. I noticed there are some API changes. Many classes that used to be in org.drools appear to be now in org.drools.core. Also, the class DebugRuleFlowEventListener appears to no longer exist.
My question is: is there a documentation somewhere explaining the API differences between the two versions? Unless I'm missing something, it seems like they are significant and should be documented. Also, thought I was tasked with the upgrade I wasn't the one who developed so I'm far from being an expert on drools.
If there is no such documentation - can anyone advise what to do about DebugRuleflowEventListener?
Thanks, Thomas

A big focus for 6.0 was streamlining the build, deploy and loading(utilization) aspects of the system. Building and deploying now align with Maven and the utilization is now convention and configuration oriented, instead of programmatic, with sane default to minimise the configuration.
Two primary distributions consist of:
KIE Drools Workbench
Drools Editors, for rules and supporting assets.
jBPM Designer, for Rule Flow and supporting assets.
KIE Workbench
Drools Editors, for rules and supporting assets.
jBPM Designer, for BPMN2 and supporting assets.
jBPM Console, runtime and Human Task support.
jBPM Form Builder.
BAM.
Regarding API would suggest looking at OFFICIAL DOCS
There are three debug classes:
DebugAgendaEventListener
DebugRuleRuntimeEventListener
DebugWorkingMemoryEventListener
Some of the methods afterRuleFlowGroupActivated(RuleFlowGroupActivatedEvent event) and afterRuleFlowGroupDeactivated(RuleFlowGroupDeactivatedEvent event) which existed in DebugRuleFlowEventListener are moved to DebugAgendaEventListener
Hoping was able to help to some extent.
Cheers !!

Related

Running Drools on GraalVM

We have a service that uses Drools quite heavily. Would like to improve the performance by running it on GraalVM.
Is it possible to run Drools on GraalVM without using Kogito?
Disclaimer: I'm one of the Drools developers
It's definitely possible, as you've already notice, we do indeed support native image compilation with our Quarkus backend, but it'll require you to write you some code, there's no such possibility in the current codebase.
Please note that only the executable model will be supported with the static component injection (the drools-core-static module in Kogito)
Is there a reason why you don't want to use Kogito though? We are really interested. Please join our community channels or the mailing list if you want to share your feedbacks, as SO is not the best platform for it.
Thanks for your support

It is possible to Integrate Activiti with Drools rule engin

I am working on a project and trying to evaluate Drools vs Activiti.
I know there is jBPM support but my client needs Activiti for managing the business flow and I need to use rule engin for evaluating some cases.
So is it possible to integrate drools and activity. Any pointer would help.
As I mention in the Gitter channel this is totally possible.
I will recommend you to do a small PoC (Proof of Concept) to really understand the details of it. People usually underestimate the complexity of a Rule Engine like Drools. Don't get me wrong, I love Drools, but I recommend you to check the docs and one of their books ;)
Check out the chapter in Tijs Rademaker's book "Activiti in Action". It describes the drools integration for version 5.x of Activiti very completely. The concepts are still valid for Activiti 6 as well.

Process Engines for BPMN 2.0

I'm doing a comparison among all existing BPMN 2.0 Process Engines e.g. Activiti, jBPM etc.
I've prepared a list of 4 process engines which executes BPMN 2.0 given below;
Popular BPMN 2.0 compliant open-source engines:
Activiti: http://www.activiti.org/
jBPM: http://www.jboss.org/jbpm
Bonita: http://www.bonitasoft.com/
A commercial engine:
ActiveVOS: http://www.activevos.com/products
I would appreciate your help if you enhance my research by adding any existing Process Engines (for BPMN 2.0) in the above list along with the quick comparison among all.
I would prefer a very short comparison listing only important features (distinguishing features like what is possible for one and not for others, licensing, dependencies with other products like tomcat & JBoss and operating systems etc)
P.S: I've found much on Activiti vs jBPM but still your answers will be a favor.
I cannot offer you a full-fledged comparison but I can give you some pointers that might help you in your evaluation:
An "Activiti in Action" book has just been published (July
2012) and in it you will have a section reviewing other BPMN process
engines (Section 1.2.3 - Knowing the competitors).
For Activiti, there also exists since recently, a commercially-supported version called camunda fox BPM Platform. They also provide a comparison with the added-value they provide here.
I am disappointed with Activiti. It should be called Spring BPM because it doesn't work well without it. If you don't mind using Spring, then Activiti might be a better fit. If you are using JEE/CDI, then JBPM is a better fit.
I did such a research, too. Here are the key-points which were relevant for our concrete use case:
Bonita:
Bonita has a zero-coding approach which means that they provide an easy to use IDE to build your processes without the need for coding. To achieve that, Bonita has the concept of connectors. For example, if you want to consume a web service, they provide you with a graphical wizzard. The downside is that you have to write the plain XML SOAP-envelope manually and copy it in a graphical textbox. The problem with this approach is that you only can realize use cases which are intended by Bonita. If you want to integrate a system which Bonita did not developed a connector for, you have to code such a connector on your own which is very painful. For example, Bonita offers a SOAP connector for consuming SOAP web services. This connector only works with SOAP 1.2, but not for SOAP 1.1 (http://community.bonitasoft.com/answers/consume-soap-11-webservices-bonita-secure-web-service-connector). If you have a legacy application with SOAP 1.1, you cannot integrate this system easily in your process. The same is true for databases. There are only a few database connectors for dedicated database versions. If you have a version not matching to a connector, you have to code this on your own.
In addition, Bonita has no support for LDAP or Active Directory Sync in the free community edition which is quite a showstopper for a production environment. Another thing to consider is that Bonita is licensed under the GPL / LGPL license which could cause problems when you want to integrate Bonita in another enterprise application. In addition, the community support is very weak. There are several posts which are more than 2 years old and those posts are still not answered.
Another important thing is Business-IT-Alignment. Modelling processes is a collaborative discipline in which IT AND the business analysts are involed. That is why you need adequate tools for both user groups (e.g. an Eclipse Plugin for the developers and an easy to use web modeler for the business people). Bonita only offers Bonita Studio, which needs to be installed on your machine. This IDE is quite technical and not suitable for business users. Therefore, it is very hard to realize Business-IT-Alignment with Bonita.
Bonita is a BPM tool for very trivial and easy processes. Because of the zero-coding approach, the lerning curve is very low and you can start modelling very fast. You need less programming skills and you are able to realize your processes without the need of coding. But as soon as your processes become very complex, Bonita might not be the best solution because of the lack of flexibility. You only can realize use cases which are intended by Bonita.
jBPM:
jBPM is a very powerful Open Source BPM Engine which has a lot of features. The web modeler even supports prefabricated models of some van der Aalst workflow patterns (workflowpatterns.com). Business-IT-Alignment is realizable because jBPM offers an Eclipse integration as well as a web-based modeler. A bit tricky is that you only can define forms in the web modeler, but not in the Eclipse Plugin, as far as I know. To sum up, jBPM is a good candidate for using in a company. Our showstopper was the scalability. jBPM is based on the Rules-Engine Drools. This leads to the fact that whole process instances are persisted as BLOBS in the database. This is a critial showstopper when you consider searching and scalability.
In addition, the learning curve is very high because of the complexity. jBPM does not offer a Service Task like the BPMN-Standard suggests In contrast, you have to define your own Java Service tasks and you have to register them manually in the engine, which results in quite low level programming.
Activiti:
In the end, we went with Activiti because this is a very easy to use framework-based engine. It offers an Eclipse Plugin as well as a modern AngularJS Web-Modeler. In this way, you can realize Business-IT-Alignment. The REST-API is secured by Spring Security which means that you can extend the Engine very easily with Single Sign-on features. Because of the Apache License 2.0, there is no copyleft which means you are completely free in terms of usage and extensibility which is very important in a productive environment.
In addition, the BPMN-coverage is very good. Not all BPMN-elements are realized, but I do not know any engine which does that.
The Activiti Explorer is a demo frontend which demonstrates the usage of the Activiti APIs. Since this frontend is based on VAADIN, it can be extended very easily. The community is very active which means that you can get help very fast if you have any problems.
Activiti offers good integration points for external form-technologies which is very important for a productive usage. The form-technologies of all candidates are very restrictive. Therefore, it makes sense to use a standard form-technology like XForms in combination with the Engine. Even such more complex things are realizable via the formKey-Attribute.
Activiti does not follow the zero-coding approach which means that you will need a bit of coding if you want to orchestrate services. But even the communication with SOAP services can be achieved by using a Java Service Task and Apache CXF. The coding effort is low.
I hope that my key points can help by taking a decision. To be clear, this is no advertisment for Activiti. The right product choice depends on the concrete use cases. I only want to point out the most important points in our project.
Best regards Ben
Nommy, you should take a look at Roubroo - a process engine built to natively support BPMN 2.0. It does not have the legacy of an older process engine being retrofitted to support the new standard. It support BPMN 2.0 execution semantics including the IOR gateway, which I think is the key to way business processes are defined in a networked graph. jBPM and Activiti are based on the underlying PVM, which has great support for some workflow patterns but not for others. Take a look at this research paper : http://eprints.qut.edu.au/14320/1/14320.pdf
and http://www.workflowpatterns.com/evaluations/opensource/
In my opinion currently Camunda BPM Platform the leader in the open source field.
And you mentioned Open Source?
So try camunda if you like:
- Clean BPMN focused engine (Shared, Embedable or "remote")
- Clean and working REST API
- Out of the box Platform with basic administration tools, and development ready API's
- Biggest open-source community (my persnoal oppinion)
- Best of Breed approach in the java eco-system.
- If you like Java.
- If you want to that your Processes get accepted by your IT crowd.
http://www.camunda.com/fox/product/details/
jBPM5 is agnostic to the environment, it doesn't depend on JBoss, you can run it in every Application Server, Servlet Container or a SE environment. jBPM5 is licensed with the Apache Software License V2 which I believe that is a really good idea.
You can of course find more information in the official page.
Cheers
Regarding jBPM:
jBPM is an open-source workflow engine written in Java that can execute business processes described in BPMN 2.0 (or its own process definition language jPDL in earlier versions). It is released under the ASL (or LGPL in earlier versions) by the JBoss company
It includes,
Strong and powerful integration with business rules and event processing.
Process collaboration, monitoring and management through the Guvnor repository and the management consoles.
Human interaction using an independent WS-HT human task service.
In essence jBPM takes graphical process descriptions as input. A process is composed of tasks that are connected with sequence flows. Processes represent an execution flow. The graphical diagram (flow chart) of a process is used as the basis for the communication between non-technical users and developers.
Take also a look at Imixs-Workflow which is a human-centric workflow engine. Unlike the usual engines, Imixs workflow is characterised by strong support for user-centric.
Human-centric business process management means supporting human skills, activities and collaboration in a task-oriented manner. With such a Workflow engine you can protect and securely distribute business data within an event-driven BPM architecture based on the BPMN 2.0 standard.
The Imixs-Workflow engine is open source and can be integrated in Jakarta EE oder deployed out of the box with a Microservice running in a Docker container
Take a look at Zeebe.io - a modern, cloud-native workflow engine with first-class Node.js support.

Sample Application Using Drools5

I am working on the Drools5.I am new to this Drools.I need a sample working example for this Drools.For this i have googled it alot but i did not find the correct one.If anyone has an idea can give me the reply.
Since I'm on the same boat as you are, I've searched for learning material quite a bit. Here are my resources:
http://www.jboss.org/drools For the general portal for the project.
Since this project has nicely modularized submodules, here they are:
Drools Guvnor for the Management Module that is used to manage packages of rules and POJOs with versions and also for deployment of snapshots for external usage.
Drools Expert for the expert systems core of the project. Here you can get a first look at how rule processing works under drools.
Drools jBPM5 for business workflow process modeling and integration.
Drools Fusion for Complex Event Processing (CEP) with which you can do all timeconstraint sorts of pattern matching you could think of (my favorite by the way ;).
Drools Planner for planning and business resource optimization.
For each of them, there is a complete and in my opinion high quality documentation out. In there you can really get a hands on an start digging in. You could also start working through one or the other of my personal list:
Getting started with drools fusion, by TheJavaDude
Creating Category, Package, Declarative Model, Rules And Snapshot In Drools Guvnor[Video]
Mark Proctors introduction to drools at FOSDEM[Video]
I hope this helps.
Greetings,
Kjellski

understanding working of Drools guvnor

can any one plz let me know that how drool guvnor work i went to guvnor documentation but couldn't understand the core logic of how rules are processed and how we can use drools guvnor in coherence with java code
Basically i want to know how java code interacts with drools guvnor api.
There is very less documentation about latest drool 6.
I suggest you watch this presentation by Mark Proctor on drools 6 (Drools Project Lead at Red Hat) and visit his Youtube Channel to watch screencasts of drools workbench and tutorials on building example applications.